Characterization, cloning and functional expression of novel xylanase from Thermomyces lanuginosus SS-8 isolated from self-heating plant wreckage material.

Extracellular cellulase free xylanase from Thermomyces lanuginosus sp. SS-8, isolated from self heating plant wreckage material was identified as β-1,4-endo-xylanase precursor, a monomer of 21.3 kDa with no carbohydrate residue.

Characterization of deamidation of barstar using electrospray ionization quadrupole time-of-flight mass spectrometry, which stabilizes an equilibrium unfolding intermediate.

Deamidation of asparaginyl residues is a common posttranslational modification in proteins and has been studied extensively because of its important biological effects, such as those on enzymatic activity, protein folding, and proteolytic degradation. However, characterization of the sites of deamidation of a protein has been a difficult analytical problem. In this study, mass spectrometry has been used as an analytical tool to characterize the deamidation of barstar, an RNAse inhibitor.

Rapid comparison of a candidate biosimilar to an innovator monoclonal antibody with advanced liquid chromatography and mass spectrometry technologies.

This study shows that state-of-the-art liquid chromatography (LC) and mass spectrometry (MS) can be used for rapid verification of identity and characterization of sequence variants and posttranslational modifications (PTMs) for antibody products. A candidate biosimilar IgG1 monoclonal antibody (mAb) was compared in detail to a commercially available innovator product. Intact protein mass, primary sequence, PTMs, and the micro-differences between the two mAbs were identified and quantified simultaneously.

Characterization of recombinant protein mutants by top-down sequencing using quadrupole time-of-flight mass spectrometry.

Top-down sequencing using quadrupole time-of-flight mass spectrometry is used as a direct way of locating the mutated sites of recombinant proteins and posttranslational modification in a protein. Several mutants of barstar, expressed in E.coli, were confirmed by analyzing the fragmentation pattern of mutants.

Top-down approach of completely sequencing a 4.9 kDa recombinant peptide using quadrupole time-of-flight mass spectrometry.

A recombinant peptide (near the C-terminal region of head involution defective protein) of 4.9 kDa has been completely sequenced and characterized using medium-resolution mass spectrometry (QTOF). The observed difference in the experimental mass and the theoretical mass is due to beta-mercaptoethanol adduct formation on the cysteine residue.